Magnetic false twist spindle

ABSTRACT

A magnetic false twist spindle comprising a support formed from magnetic material, a single driving roller mounted in this support, at least two magnets located in said support with the poles or associated pole pieces adjacent the periphery of the roller near the axial ends thereof and a spindlette, having a false twist locking means, the spindlette being held in frictional contact with the single driving roller by means of the magnets, the magnetic path being completed by the spindlette and the support.

0 United States Patent [15] 3,673,782 Raschle 1 1 July 4, 1972 541 MAGNETIC FALSE TWIST SPINDLE 3,355,871 12/1967 Mattingly ..57 77.45 3,355,870 12/1967 Mattingly ..57/77.45 [72] Inventor. Josef Raschle, Butschw1l,Sw1tzerland 3,304,706 2/1967 Mattinglym" WW/77.45 [73] Assignee: Moulinage & Retorderie De Chavanoz, 3,232,037 2/1966 Crouzet ..57/77.45 Chavanoz, France 3,403,566 10/1968 Mattingly ..57/77.45 X

[22] Fled: July 1970 Primary Examiner-Donald E. Watkins [21] Appl. No.: 59,552 Attorney-Sherman and Shalloway [30] Foreign Application Priority Data [57] ABSTRACT A magnetic false twist spindle comprising a support formed Aug. 1, 1969 France ..69/26460 from magnetic material asingle driving roller mounted in this support, at least two magnets located in said support with the [52] U.S. Cl 57/77.45 poles or associated pole pieces adjacent the Periphery of the [51] Int. Cl. ...D0lh 7/92, D02g l/04 [58] new of Search 57/77 45 roller near the axial ends thereof and a spmdlette, havmg a false twist locking means, the spindlette being held in frictional contact with the single driving roller by means of the [56] References cued magnets, the magnetic path being completed by the spindlette UNITED STATES PATENTS and the pp 3,308,614 3/1967 Stahlecker.....,. ..57/77.45 14 Claims, 9 Drawing Figures PA'TENTEnJum m2 3. 673,782

SHEET 3 BF 3 Inventor A Home y MAGNETIC FALSE TWIST SPINDLE The present invention relates to magnetic false twist spindles, more particularly the present invention relates to a magnetic mono-roller false twist spindle supported by a simple magnet.

In the texturing of textile threads or yarns by false twist, spindles are used which impart false twist to the yarn, the twist travelling up in the yarn towards a healing element acting on the yarn when the latter is in the twisted state,.the twist already introduced being set during the subsequent cooling step.

Numerous devices are known for imparting false twist. As a rule, they comprise a tubular spindle which is provided with means for locking the twist and with means for rotating the spindle.

In recent years, spindles have been developed in which the spindlette is drawn magnetically against the drive means, consisting originally of two rollers or pulleys having slightlyoverlapping parallel flanges or cheeks and retaining the spindlette due to their co-operation. v

Proceeding from an extremely old idea relating to an uptwister spindle drawn magnetically against a rotating disc, a magnetic false twist spindle of the so-called mono-roller type was developed, wherein the spindlette is attracted and centered by magnetic means, both axially and laterally, against a single flanged roller, the spindle floating without support other than the roller, whereas the magnetic flux acts on the ends of the spindle without an intermediary of any kind. This device has permitted the achievement of rotational speeds of several hundreds of thousands of revolutions of the spindle per minute, and even more, with at the same time a relatively reduced consumption of driving power.

The device described, which employs a horseshoe magnet, nevertheless has the disadvantage that the magnetic field is closed through the driving roller, thus involving a risk of the generation of Foucault currents, accompanied by braking and heating effects. In order to obviate these disadvantages, it has been envisaged to use complicated magnet shapes which have the disadvantage that they are extremely costly.

Briefly, according to the invention there is provided a magnetic false twist spindle comprising a support formed of magnetic material, a single driving roller mounted for rotation with respect to said support, at least two magnets located in openings in said support, with their poles or with associated pole pieces adjacent the periphery of the roller near the axial ends thereof and a spindlette, provided with false twist locking means, held in frictional contact by the magnets, the magnetic path being completed by the spindlette and the support.

It is the primary object of this invention to provide an improved mono-roller magnetic false twist spindle.

It is a further object to provide a magnetic false twist spindle which does not generate harmful Foucault currents.

It is a still further object to provide a magnetic false twist spindle having a magnet of a relatively simple and uncomplicated shape.

Still further objects and advantages of the magnetic false twist spindle of this invention will become apparent from the following more detailed description thereof.

In one embodiment of the apparatus of this invention only two magnets are provided, the magnets being mounted substantially coaxially in the same magnetic sense, with the north pole of one magnet near one axial end of the roller and the south pole of the other magnet near the other axial end of the roller.

In a second embodiment two pairs of magnets are provided, the two magnets of a pair being mounted substantially coaxially with the two magnets of the other pair, and in the same magnetic sense, with the north poles of one pair near one axial end of the roller and the south poles of the other pair near the other axial end of the roller.

In another embodiment only two magnets are provided, and are mounted substantially parallel to one another and parallel to and on opposite sides of the spindlette, magnetic pole pieces carried by the support being located one near each axial end of the roller.

The invention will be more readily understood from the following description given purely by way of example, reference being made to the accompanying drawings, in which:

FIG. 1 is a side elevation of one embodiment of spindle according to the invention;

FIGS. 2A to 5A are side elevations of four further embodiments; and

FIGS. 2B to 5B are plan views of the spindles of FIGS. 2A-5A respectively.

In the embodiment of FIG. 1 a spindlette l is drawn magnetically against a single roller or pulley 2 which is formed with flanges 3 and 4. The spindlette comprises false twist locking means, for example crossed bars, and is formed with a central ring 5 associated with the groove in the pulley 2 between the two flanges 3 and 4. The pulley 2 is mounted on a shaft 6 having a drive pulley 7. The shaft 6 is mounted by means of precision bearings 8 and 9 in two bearings 10 and 11 in a support 12 of magnetic material having an upper arm 13 for the upper bearing 10 and a lower arm 14 for the lower bearing 11. The shaft abuts in the bearing 10 but extends through the bearing 11, the pulley 7 being disposed externally of the support 12, which is mounted on a frame (not shown) by means of two rods 15 and 16.

The upper arm 13 of the support 12 carries a simple prismatic magnet 18 having a bevelled lip 20 acting as a pole piece, and the lower arm 14 of the support 12 carries a prismatic magnet 19 coaxial with magnet 18 and having a bevelled lip 21 acting as a pole piece.

The ends of the spindlette l are disposed opposite the lips 20 and 21 with an air gap of minimum size.

The magnetic circuit is indicated by arrows F F F F it may also be in the opposite direction.

By reason of this arrangement, the centering of the spindle is perfect, both axially and laterally.

There is no magnetic flux through the roller or pulley, if the latter is made from an inert material.

Referring to FIGS. 2A and 28, a false twist spindlette 31 of magnetizable material is magnetically drawn towards a roller 32 provided with two flanges 33 and 34. The spindlette is provided with known twist locking means, for example crossed bars. As in FIG. 1, at its center, the spindlette 31 carries a stabilizing ring 35.

Associated with the roller 32 is a support in the form of a rectangular window 36 having, half-way up, a portion exhibiting a marked cranked portion 36', which overlies the axial ends of the flanges 33 and 34 in such manner that the plane of the main portion of the window intersects the roller sufiiciently near to the axis 32 of the roller 33.

The said window carries two pairs of magnets 37, 38 and 39, 40 of simple shape, such as prismatic or cylindrical shape, arranged in the same magnetic sense so that a north pole is situated opposite a south pole identically in each case. The magnets 37, 39 and also 38, 40 carry a common nose or pole piece 41 which is rounded or bevelled at the end 42. The apices of these ends are in a plane very close to that of the axis of the spindlette, while of course leaving the space required for the axial passage of the yarn to which false twist is to be imparted.

The magnetic flux is double and circulates in the direction of the two arrows F F (or in the opposite direction).

The magnetic system may for example be of cast iron. The window may be attached separately or may be integral with the support of the roller carrying element.

In the embodiment according to FIGS. 3A and 33, like reference numerals have been used but increased by 20 as compared with FIGS. 2A and 2B. The window is only half that of the preceeding Figures and there is only one pair of magnets. The magnetic flux is in the direction of arrow F (or in the opposite direction). The magnetic system may be based on oxides.

In the embodiment according to FIGS. 4A and 48, again the reference numerals have been increased by 20. Here, the window 76 is complete, as in the first example, but there is only one pair of magnets 82, 83, having pole pieces 82', 83' and centered relatively to the spindlette 71. The magnets are bevelled at the front 84.

g In the embodiment according to FIGS. 5A and 5B, the reference numerals have been increased by a further 20. Here again there is a complete window 96 but there is only one pair of magnets 105; 106, disposed on the vertical members of the frame 96. The magnetic flux is in the direction of arrows F and F, and is centered by the pole pieces 102','l03.

What we claim is:

l. A magnetic false twist spindle assembly comprising a support member; a driving roller mounted on said support; at least two magnets carried by said support member and forming a pair of poles, each disposed adjacent the periphery of said roller near opposite axial ends thereof; and a spindlette having false twist locking means and being held in contact with said roller by a magnetic field established by said magnets, said support member providing a continuous path for completing said magnetic field through said support member and said spindlette.

2. An assembly as recited in claim 1 wherein said magnets are of a simple prismatic shape.

3. An assembly as recited in claim 1 wherein only two mag nets are provided, said magnets being mounted substantially coaxially in the same magnetic sense, with the north pole of one magnet near one axial end of said roller and the south pole of the other magnet near the other axial end of said roller.

4. An assembly as recited in claim 1 wherein two pairs of magnets are provided, the two magnets of one pair being mounted substantially coaxially with the two magnets of the other pair and in the same magnetic sense, with the north poles of said one pair near one axial end of said roller and the south poles of said other pair near the other axial end of said roller.

5. An assembly as recited in claim 1 wherein only two magnets are provided, said magnets being mounted substantially parallel to one another and parallel to and on opposite sides of said spindlette to define magnetic pole pieces carried by the support member and located one near each axial end of said roller.

6. An assembly as recited in claim 1 wherein said support member has two arms extending across the axial ends of said roller and provided with bearings for said roller. 1

7. An assembly as recited in claim 1 wherein said support member has a part extending parallel to the axis of said roller and externally of the periphery thereof, and a portion extending across each axial end of said roller and carrying said poles.

8. An assembly as recited in claim 7 wherein said part includes two parallel side arms of a window, said side arms being on opposite sides of said spindlette.

9. An assembly as recited in claim 1 wherein said support member has bevelled pole pieces provided adjacent the ends of said spindlette.

10. An assembly as recited in claim 1 wherein said support member is formed of cast iron.

11. An assembly as recited in claim 1 wherein said support member is formed of a magnetic oxide.

12. An assembly as recited in claim 1 wherein said magnets are of a simple cylindrical shape.

13. An assembly as recited in claim 1 wherein said poles are spaced from the ends of said spindlette by a pair of air gaps,

said pair of air gaps being the only air gaps in said magnetic path.

14. An assembly as recited in claim 1 wherein said support member has a pair of arms extending across the axial ends of said roller for supporting said magnets and has a part extending parallel to the axis of said roller interconnecting said arms, said support member being integrally formed of a magnetizable material. 

1. A magnetic false twist spindle assembly comprising a support member; a driving roller mounted on said support; at least two magnets carried by said support member and forming a pair of poles, each disposed adjacent the periphery of said roller near opposite axial ends thereof; and a spindlette having false twist locking means and being held in contact with said roller by a magnetic field established by said magnets, said support member providing a continuous path for completing said magnetic field through said support member and said spindlette.
 2. An assembly as recited in claim 1 wherein said magnets are of a simple prismatic shape.
 3. An assembly as recited in claim 1 wherein only two magnets are provided, said magnets being mounted substantially coaxially in the same magnetic sense, with the north pole of one magnet near one axial end of said roller and the south pole of the other magnet near the other axial end of said roller.
 4. An assembly as recited in claim 1 wherein two pairs of magnets are provided, the two magnets of one pair being mounted substantially coaxially with the two magnets of the other pair and in the same magnetic sense, with the north poles of said one pair near one axial end of said roller and the south poles of said other pair near the other axial end of said roller.
 5. An assembly as recited in claim 1 wherein only two magnets are provided, said magnets being mounted substantially parallel to one another and parallel to and on opposite sides of said spindlette to define magnetic pole pieces carried by the support member and located one near each axial end of said roller.
 6. An assembly as recited in claim 1 wherein said support member has two arms extending across the axial ends of said roller and provided with bearings for said roller.
 7. An assembly as recited in claim 1 wherein said support member has a part extending parallel to the axis of said roller and externally of the periphery thereof, and a portion extending across each axial end of said roller and carrying said poles.
 8. An assembly as recited in claIm 7 wherein said part includes two parallel side arms of a window, said side arms being on opposite sides of said spindlette.
 9. An assembly as recited in claim 1 wherein said support member has bevelled pole pieces provided adjacent the ends of said spindlette.
 10. An assembly as recited in claim 1 wherein said support member is formed of cast iron.
 11. An assembly as recited in claim 1 wherein said support member is formed of a magnetic oxide.
 12. An assembly as recited in claim 1 wherein said magnets are of a simple cylindrical shape.
 13. An assembly as recited in claim 1 wherein said poles are spaced from the ends of said spindlette by a pair of air gaps, said pair of air gaps being the only air gaps in said magnetic path.
 14. An assembly as recited in claim 1 wherein said support member has a pair of arms extending across the axial ends of said roller for supporting said magnets and has a part extending parallel to the axis of said roller interconnecting said arms, said support member being integrally formed of a magnetizable material. 